Right. Well, we can agree to disagree that we can derive ethics from observations of the natural world. We might be able to do that, if we were more enlightened or had greater resources at disposal, but we are far from being there. Human beings are pretty fallible and irrational, which is why we still need tradition, even if tradition needs to be questioned periodically.
For instance, I think that the most heinous, most damaging ideas tend to come from rationalist philosophers, because with the right set of first principles you can justify anything. In fairness, you mentioned empiricism (observations), however, how are you going to conduct studies on what's "murder"? All kinds of social experiments ended in disaster, we can't even do good studies on nutrition without spending a lot of resources, and studies that can knowingly hurt individuals are deemed as immoral and thus forbidden.
In general, I think that at this point, "secular ethics based on observations" is a pipe dream. At least until we'll be able to simulate society somehow, and in the meantime, mathematical models are bullshit with a really poor prediction rate. Also, even if science would unequivocally suggest that getting rid of certain groups of people would be a net benefit, I'd still have a problem with it. As in my view, policies baked by current scientific findings and that supposedly benefit society, can still be evil. At the dawn of the 20th century, it probably took a lot of courage to speak against race science and eugenics.
I also have this opinion that ALL people are religious, and by religion I mean beliefs that are non-falsifiable, or close to it, and in this definition religion does not require the existence of a God.
> When a government passes a law that prohibits transgender people from obtaining healthcare to treat their condition, that is a violation of their natural right to live.
Again, I'm all for transgender people having all the healthcare they need. However, access to healthcare is not a natural right for the simple fact that somebody else has to pay for it and the tradition is not fully established. Consider how free universal healthcare is only possible in affluent countries with a high GDP. "Taxing the rich" is also only a solution in countries that have enough rich people to tax. The public budget is never unlimited, and there are always priorities.
Countries like the US could provide free universal healthcare, no doubt about it. It is also my impression that US's healthcare is corrupt, and they could probably do it without increasing current spending, if the corruption was dealt with. But if the public spending goes up (big if), then it's the taxpayers that have to agree with it, and they do that by voting. Which is a sad state of affairs, as all would benefit from universal healthcare, but it underlines the fact that free healthcare is a privilege.
Note that I'm saying this as an asthmatic, a chronic condition for which I need medication, without which I'd be unable to live. I do have access to it, but I don't consider it a right, but rather a blessing to live in a century in which I can have access to it. I might have been born 30 years earlier.